Golf balls having improved short game performance

ABSTRACT

Golf balls having three-dimensional shaped fret areas and methods of making the same are disclosed. The three-dimensional shaped fret areas have at least three edges that meet at an apex point or an apex surface. The three-dimensional shaped fret areas may have a three-dimensional irregular pyramid shape or a three-dimensional truncated irregular pyramid shape. The three-dimensional shaped fret areas create golf balls having increased traction upon impact with the playing surface.

FIELD OF THE INVENTION

The present disclosure relates generally to golf balls. Moreparticularly, the present disclosure relates to golf balls having fretareas that are designed to provide an increase in traction with aplaying surface.

BACKGROUND OF THE INVENTION

A golf ball typically includes an outer spherical surface withdepressions or dimples on the outer surface. The portions of the outersurface between the dimples are commonly referred to as fret areas andform the un-dimpled surface of the golf ball. The dimples perturb theair flow surrounding the golf ball and create air turbulence as the ballmoves through the air. The dimples are intended to create theappropriate amount of turbulence to reduce the aerodynamic drag andoptimize golf ball performance.

Unlike dimples on the golf ball, the fret areas have the same curvatureas a phantom sphere of the same radius as the golf ball. This causes thegolf ball fret area to have a smooth texture. Since the fret area isoften the first part of the golf ball to impact the playing surface, asmooth fret area does not optimize a golf ball's ability to grip theplaying surface and reduce roll out. This is why golf shoe outsoles aregenerally equipped with cleats (or metal spikes in some cases) that areintended to prevent slipping during a player's golf swing and provideimproved traction while traversing hills on the golf course. If theaforementioned shoe outsoles were smooth, it would compromise theplayer's ability to grip the terrain and ultimately lead to slipping.Similar to smooth shoe outsoles, the smooth fret areas compromise thegolf ball's ability to grip the playing surface and reduce roll out.Reducing the amount of roll is desirable especially on shots where thegolfer wishes to stop the ball as close to its landing position aspossible but is unable to impart a high spin rate on the golf ball dueto undesirable conditions of the golf shot.

Accordingly, there remains a need for golf balls having fret areas thatcan reduce the amount of roll out on a playing surface compared to thatof golf balls having traditional fret areas impacting the playingsurface with similar landing conditions.

SUMMARY OF THE INVENTION

The problems expounded above, as well as others, are addressed by thefollowing inventions, although it is to be understood that not everyembodiment of the inventions described herein will address each of theproblems described above.

In some embodiments, a golf ball having a substantially sphericalsurface is provided, the golf ball including a plurality of dimples onthe spherical surface and a plurality of fret areas definedtherebetween, wherein at least one fret area on the spherical surfaceincludes a three-dimensional irregular pyramid shape having at leastthree edges meeting at an apex point, and wherein the three-dimensionalirregular pyramid shape has a height defined as the radial distancebetween the apex point and a phantom sphere having a radius. In someembodiments, the three-dimensional irregular pyramid shaped fret area issurrounded by three dimples of the plurality of dimples. In otherembodiments, the radius is greater than about 0.84 inches. In stillother embodiments, the radius is less than about 0.84 inches and the sumof the radius and the height is greater than about 0.84 inches. Infurther embodiments, the three-dimensional irregular pyramid shape has atotal surface area of about 0.001 square inches to about 0.008 squareinches. In still further embodiments, the height ranges from about 0.002inches to about 0.025 inches.

In other embodiments, a golf ball having a substantially sphericalsurface is provided, the golf ball including a plurality of dimples onthe spherical surface and a plurality of fret areas definedtherebetween, wherein at least one fret area on the spherical surfaceincludes a three-dimensional truncated irregular pyramid shape having atleast three edges meeting at an apex surface, wherein the apex surfaceis a planar surface having a center of mass coincident with an apexpoint of the three-dimensional truncated irregular pyramid shape, andwherein the three-dimensional truncated irregular pyramid shape has aheight defined as the radial distance between the apex surface and aphantom sphere having a radius, and wherein the apex surface comprises apolygonal shape. In other embodiments, the apex surface has a polygonalshape formed of at least three edges. For example, the apex surface mayhave a triangular shape. In still other embodiments, the apex surfaceincludes a non-polygonal shape formed of a combination of line segmentsand curvatures. In further embodiments, the apex surface has a surfacearea ranging from about 0.0002 square inches to about 0.001 squareinches. The surface area of the apex surface may account for about 5percent to about 15 percent of the total surface area of thethree-dimensional truncated irregular pyramid shape. In still furtherembodiments, the three-dimensional truncated irregular pyramid shapedfret area is surrounded by three dimples of the plurality of dimples. Inyet further embodiments, the height ranges from about 0.005 inches toabout 0.020 inches. In some embodiments, the radius of the phantomsphere is (i) greater than about 0.84 inches or (ii) less than about0.84 inches but the sum of the radius and the height is greater thanabout 0.84 inches.

In further embodiments, a method of forming a three-dimensional shapedfret area on a golf ball is provided, the method including selecting aset of three neighboring dimples on a surface of the golf ball, whereineach dimple has a center; drawing a dimple line from the center of eachdimple to the center of each of its neighboring dimples to form atriangle, wherein the triangle defines a fret area on the golf ball inwhich the three-dimensional shaped fret area will be formed; identifyingan edge origin along each of the dimple lines of the triangle, whereinthe edge origin is a point along the dimple line that is located outsidethe perimeters of each of the three neighboring dimples; identifying acentroid of the triangle, wherein the centroid defines an apex of thefret area; and drawing an edge line from each edge origin to the apex toform the three-dimensional shaped fret area. In some embodiments, themethod further includes drawing an apex surface about the apex, whereinthe apex surface is a planar surface having a center of mass coincidentwith the apex. In other embodiments, the apex surface has a polygonalshape comprising at least three edges. In still other embodiments, thestep of drawing the edge line further includes drawing two or more edgelines from each edge origin to the apex. In yet other embodiments, thethree-dimensional shaped fret area includes a three-dimensionalirregular pyramid shape.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the invention can be ascertained fromthe following detailed description that is provided in connection withthe drawings described below:

FIG. 1 is a front perspective view of a golf ball showing a plurality ofdimples and fret areas.

FIG. 2 is a schematic diagram showing reaction forces of a playingsurface on a golf ball.

FIG. 3 is an enlarged view of a portion of a golf ball surface having athree-dimensional shaped fret area designed in accordance with oneembodiment of the present disclosure.

FIG. 4 is an enlarged view of a portion of a golf ball surface having athree-dimensional shaped fret area designed in accordance with anotherembodiment of the present disclosure.

FIG. 5 is an enlarged view of a portion of a golf ball surface having athree-dimensional shaped fret area designed in accordance with stillanother embodiment of the present disclosure.

FIG. 6 is an enlarged view of a portion of a golf ball surface having athree-dimensional shaped fret area designed in accordance with yetanother embodiment of the present disclosure.

FIG. 7 is an enlarged view of a portion of a golf ball surface having athree-dimensional shaped fret area designed in accordance with stillanother embodiment of the present disclosure.

FIG. 8A is a schematic diagram illustrating the fret height H between aphantom sphere and an apex point of the three-dimensional shaped fretareas designed in accordance with the present disclosure.

FIG. 8B is a schematic diagram illustrating the fret height H between aphantom sphere and an apex surface of the three-dimensional shaped fretareas designed in accordance with the present disclosure.

FIG. 9A is a schematic diagram showing tangency lines drawn between twoneighboring dimples.

FIG. 9B is a schematic diagram showing tangency lines drawn between twonon-neighboring dimples.

FIG. 10 is an enlarged view of a portion of a golf ball surface showinga reference triangle formed by a set of three neighboring dimple lineswith an apex point formed therein in accordance with an exemplary methodof the present disclosure.

FIG. 11 is an enlarged view of the portion of the golf ball surfaceshown in FIG. 10 illustrating a three-dimensional shaped fret areadesigned in accordance with an exemplary method of the presentdisclosure.

FIG. 12 is an enlarged view of a portion of a golf ball surface showinga reference triangle formed by a set of three neighboring dimple lineswith an apex surface formed therein in accordance with an exemplarymethod of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art of this disclosure. It will be furtherunderstood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andshould not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein. Well known functions or constructions maynot be described in detail for brevity or clarity.

The terms “about” and “approximately” shall generally mean an acceptabledegree of error or variation for the quantity measured given the natureor precision of the measurements.

Numerical quantities given in this description are approximate unlessstated otherwise, meaning that the term “about” or “approximately” canbe inferred when not expressly stated.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well (i.e., at least one of whatever the article modifies),unless the context clearly indicates otherwise.

The terms “first,” “second,” “third,” and the like are used herein todescribe various features or elements, but these features or elementsshould not be limited by these terms. These terms are only used todistinguish one feature or element from another feature or element.Thus, a first feature or element discussed below could be termed asecond feature or element, and similarly, a second feature or elementdiscussed below could be termed a first feature or element withoutdeparting from the teachings of the present disclosure.

Golf Balls Having Three-Dimensional Shaped Fret Areas

Referring to FIG. 1 , a golf ball 10 having a spherical core (not shown)and a cover 4 is shown. Numerous dimples 6 are formed on the cover 4 ofthe golf ball 10. The upper curved portion of the cover 4 extending fromdimple to dimple is known as a fret area 8. The present disclosureprovides golf balls having a secondary surface texture in the fret areasof the golf ball. In some embodiments, the fret areas have athree-dimensional shape. The three-dimensional shaped fret areas creategolf balls having increased traction upon impact with the playingsurface. As illustrated in the free body diagram of FIG. 2 , Frepresents the force a golf ball exerts on the ground, while FN andtraction force FT represent the reaction forces of the playing surfaceon the golf ball. By increasing the traction force FT with the use ofthree-dimensional shaped fret areas, the golf ball can better grip theplaying surface upon impact. This is especially desirable for shotswhere the golfer wishes to minimize the amount of roll but is unable toimpart a high spin rate on the golf ball.

In some embodiments, the fret areas of the present disclosure aredesigned as three-dimensional irregular pyramids. As used herein, a“three-dimensional irregular pyramid” refers to a fully enclosedthree-dimensional shape having one or more faces that resemble a polygonand a base having curved edges. The regions where two faces of the shapemeet to form a line segment are known as the edges and the points wheretwo or more edges meet are known as the vertices of the shape. In someembodiments, the three-dimensional irregular pyramid shaped fret areashave at least three edges. In other embodiments, the three-dimensionalirregular pyramid shaped fret areas may have four or more edges. Instill other embodiments, the three-dimensional irregular pyramid shapedfret areas may have six or more edges. In yet other embodiments, thethree-dimensional irregular pyramid shaped fret areas may have nine ormore edges. In still further embodiments, the three-dimensionalirregular pyramid shaped fret areas may have twenty or more edges. Thethree-dimensional irregular pyramid shaped fret areas can generally haveany number of edges depending on the desired appearance of the fretarea.

The three-dimensional irregular pyramid shaped fret areas may also haveany number of vertices, one of which is an apex (i.e., the highest pointof the shape). In some embodiments, the three-dimensional irregularpyramid shaped fret areas have three or more vertices. In still otherembodiments, the three-dimensional irregular pyramid shaped fret areashave five or more vertices. In yet other embodiments, thethree-dimensional irregular pyramid shaped fret areas have ten or morevertices. In still other embodiments, the three-dimensional irregularpyramid shaped fret areas have twenty or more vertices. As will beappreciated by one of ordinary skill in the art, the total number ofvertices of the three-dimensional irregular pyramid shaped fret areaswill depend on the number of edges utilized.

Each of the three-dimensional irregular pyramid shaped fret areas has anapex. The apex is defined as the vertex at the top of thethree-dimensional irregular pyramid shaped fret area (opposite the baseor the surface of the golf ball). In some embodiments, the apex of thethree-dimensional irregular pyramid shaped fret area is a point. Thatis, the edges of the three-dimensional irregular pyramid shape meet atan apex point.

FIGS. 3 and 4 illustrate various three-dimensional irregular pyramidshaped fret areas having an apex point according to the presentdisclosure. FIG. 3 shows a three-dimensional irregular pyramid shapedfret area 20 positioned between three neighboring circular dimples D₁,D₂, D₃ on the surface of the golf ball 10. The three-dimensionalirregular pyramid shaped fret area has three edges. The three edges meetat a single apex point A. As illustrated in FIG. 3 , thethree-dimensional irregular pyramid shaped fret area 20 resembles apyramid shape. FIG. 4 shows a three-dimensional irregular pyramid shapedfret area 30 positioned between three neighboring circular dimples D₁,D₂, D₃ on the surface of the golf ball 10 according to anotherembodiment. The three-dimensional irregular pyramid shaped fret area 30has nine total edges, six of which form faces resembling that of atriangle. The three remaining edges connect the edges forming thetriangular-like faces to a single apex point A.

In other embodiments, the three-dimensional irregular pyramid shapedfret areas can have an apex surface. In this embodiment, the fret areasmay be referred to as three-dimensional truncated irregular pyramidshaped fret areas. The truncated irregular pyramid shaped fret areasinclude a surface having a center of mass that is positioned at the apexpoint. The edges of the shape can meet at the perimeter of the apexsurface such that the truncated irregular pyramid shaped fret area has aplanar upper portion (as opposed to a peak formed by the apex pointdiscussed above). The apex surface may have any shape that allows forthe surface to be centered at the apex point of the shape. In someembodiments, the apex surface is a polygonal shape having at least threeedges. Suitable polygonal shapes for the apex surface include, but arenot limited to, triangles, quadrilaterals, pentagons, hexagons,heptagons, octagons, nonagons, decagons, hendecagons, dodecagons,triskaidecagons, tetradecagons, pentadecagons, hexadecagons,heptadecagons, octadecagons, nonadecagons, icosagons, and the like. Infurther embodiments, the apex surface can have a non-polygonal shape.For instance, the apex surface may have a shape including one or morecurvatures, such as a circle. Other suitable curved shapes include, butare not limited to, elliptical, parabolic, conic, hyperbolic,sinusoidal, or any combination of these curves. In still otherembodiments, the apex surface may have a shape including one or moreline segments and one or more curvatures. The size of the apex surfacemay vary so long as the area of the apex surface is less than that ofthe area of the truncated irregular pyramid shaped fret area.

FIGS. 5, 6, and 7 illustrate various three-dimensional truncatedirregular pyramid shaped fret areas having an apex surface according tothe present disclosure. FIG. 5 shows a truncated irregular pyramidshaped fret area 40 positioned between three neighboring circulardimples D₁, D₂, D₃ on the surface of the golf ball 10. The truncatedirregular pyramid shaped fret area 40 has three edges. However, ratherthan the edges meeting at a single apex point, the edges of thetruncated irregular pyramid shaped fret area 40 meet at an apex surfaceS. In the illustrated embodiment, the apex surface S has a triangularshape, the perimeter of which is formed by three straight edges. Theedges of the truncated irregular pyramid shaped fret area 40 meet at theperimeter of the apex surface S.

FIG. 6 shows a three-dimensional truncated irregular pyramid shaped fretarea 50 positioned between three neighboring circular dimples D₁, D₂, D₃on the surface of the golf ball according to another embodiment. Similarto the truncated irregular pyramid shaped fret area shown in FIG. 5 ,the truncated irregular pyramid shaped fret area 50 has three edges thatmeet at the perimeter of an apex surface S that is triangular shaped.The apex surface S illustrated in FIG. 6 however has a smaller area thanthe apex surface S illustrated in FIG. 5 due to shorter edge lengths.

FIG. 7 shows a three-dimensional truncated irregular pyramid shaped fretarea 60 positioned between three neighboring circular dimples D₁, D₂, D₃on the surface of the golf ball according to still another embodiment.The truncated irregular pyramid shaped fret area 60 has six edges thatmeet at the perimeter of an apex surface S. The apex surface S has anon-polygonal shape including both line segments and curvatures. Asillustrated in FIG. 7 , the apex surface S has six sides, three of whichare straight edges and three of which are curvatures.

The irregular pyramid shaped and the truncated irregular pyramid shapedfret areas may have any dimensions, for example, height and surfacearea, so long as the fret areas do not interfere with the dimplesarranged on the golf ball. In one embodiment, the irregular pyramidshaped and the truncated irregular pyramid shaped fret areas have a fretheight H. The fret height H can be defined as the height of the apex,for instance, the apex point or apex surface, on the three-dimensionalirregular pyramid shaped and the truncated irregular pyramid shaped fretareas. As depicted in FIG. 8A, the fret height H (or the height of theapex) is the radial distance between a phantom sphere 12 and the apexpoint A. The phantom sphere 12 is defined as the spherical surfacecontaining fret area 8 if there were no dimples or three-dimensionalshaped fret areas. In another embodiment, as depicted in FIG. 8B, thefret height H (or the height of the apex) is the radial distance betweenthe phantom sphere 12 and the apex surface S. The phantom sphere 12 hasa radius R. In one embodiment, the radius R of the phantom sphere 12 isgreater than about 0.84 inches. In another embodiment, the radius R ofthe phantom sphere 12 is less than about 0.84 inches and the sum of theradius R and the fret height H is greater than about 0.84 inches.

In some embodiments, the fret height H may range from about 0.002 inchesto about 0.025 inches. In other embodiments, the fret height H may rangefrom about 0.005 inches to about 0.02 inches. In still otherembodiments, the fret height H may range from about 0.01 inches to about0.015 inches. In some embodiments, the three-dimensional shaped fretareas on the golf ball may all have the same fret height H. In otherembodiments, the three-dimensional shaped fret areas used on the golfball may have varying fret heights H. For instance, somethree-dimensional shaped fret areas may be shorter or taller than otherson the golf ball.

In one embodiment, the total surface area (SA) of a singlethree-dimensional shaped fret is between about 0.001 square inches andabout 0.008 square inches. In another embodiment, the total surface area(SA) of a single three-dimensional shaped fret area is between about0.002 square inches and about 0.006 square inches. In some embodiments,the three-dimensional shaped fret area has an apex surface S and thesurface area of the apex surface S is between about 0.0002 square inchesand 0.001 square inches. In other embodiments, the three-dimensionalshaped fret area has an apex surface S and the surface area of the apexsurface S is between about 0.0004 square inches and about 0.0008 squareinches. In still other embodiments, the surface area of the apex surfaceS accounts for about 5 percent to about 15 percent of the total surfacearea (SA) of the three-dimensional shaped fret area. For example, thesurface area of the apex surface S accounts for about 10 percent of thetotal surface area (SA) of the three-dimensional shaped fret area.

In some embodiments, the three-dimensional shaped fret areas may be usedat all of the fret areas on a golf ball. That is, all of the land areason the golf ball may utilize the three-dimensional shaped fret areasdisclosed herein. In other embodiments, the three-dimensional shapedfret areas may be used at only one fret area on the golf ball. In stillother embodiments, the three-dimensional shaped fret areas may be usedat a portion of the fret areas on a golf ball. For example, thethree-dimensional shaped fret areas may be used in specific locations onthe golf ball or a collection of specific locations. In one embodiment,at least about 10 percent of the fret areas on a golf ball are designedwith the three-dimensional shapes described herein. In some embodiments,at least about 20 percent of the fret areas on a golf ball are designedwith the three-dimensional shapes described herein. In otherembodiments, at least about 50 percent of the fret areas on a golf ballare designed with the three-dimensional shapes described herein. Instill other embodiments, at least about 75 percent of the fret areas ona golf ball are designed with the three-dimensional shapes describedherein. In yet other embodiments, at least about 90 percent of the fretareas on a golf ball are designed with the three-dimensional shapesdescribed herein. Indeed, as will be appreciated by one of ordinaryskill in the art, the more fret areas designed with thethree-dimensional shapes described herein, the greater the tractionforce applied to the golf ball upon impact with a playing surface.

The three-dimensional shaped fret areas may be used on golf balls havingvarying dimple geometries. In some embodiments, the three-dimensionalshaped fret areas of the present disclosure may be used on golf ballswith dimples having a circular plan shape. A “plan shape,” as usedherein, refers to the perimeter of the dimple as seen from a top view ofthe dimple, or the demarcation between the dimple and the outer surfaceof the golf ball or fret surface. In this embodiment, thethree-dimensional shaped fret areas are generally surrounded by a set ofthree neighboring dimples, as will be described in more detail below. Inother embodiments, the three-dimensional shaped fret areas may be usedon golf balls with dimples having non-circular plan shapes. For example,the plan shape may be any one of a circle, square, triangle, rectangle,oval, or other geometric or non-geometric shape. In some embodiments,the dimples on the golf ball may have a square plan shape. In thisembodiment, the three-dimensional shaped fret areas are generallysurrounded by a set of four neighboring dimples. In still otherembodiments, the dimples on the golf ball may have a plan shape definedby low frequency or high frequency periodic functions.

The three-dimensional shaped fret areas may also be used on golf ballshaving different dimple patterns. Suitable dimple patterns include, butare not limited to, polyhedron-based patterns (e.g., icosahedron,octahedron, dodecahedron, icosidodecahedron, cuboctahedron, andtriangular dipyramid), phyllotaxis-based patterns, spherical tilingpatterns, triangular dipyramids, quadrilateral dipyramids, pentagonaldipyramids, hexagonal dipyramids, and random arrangements.

Methods of Forming Three-Dimensional Shaped Fret Areas

The present disclosure also provides methods for forming thethree-dimensional shaped fret areas on a golf ball surface. In someembodiments, the method of the present disclosure involves selectingthree neighboring dimples on the golf ball. Neighboring dimples may bedetermined by first drawing two tangency lines from the center of afirst dimple to the center of a potential nearest neighboring dimple. Inaddition, a line segment is drawn connecting the center of the firstdimple to the center of the potential nearest neighboring dimple. Ifthere is no line segment that is intersected by another dimple, orportion of a dimple, then those dimples are considered to be nearestneighbors. For example, FIG. 9A shows a case where the two tangencylines and the line from one dimple center to the other dimple center donot intersect any other dimple edges, so dimple 1 and dimple 2 areconsidered nearest neighbors. Alternatively, FIG. 9B shows a case wherethe two tangency lines and the line from one dimple center to the otherdimple center intersect an alternative dimple, so dimple 1 and dimple 2are not considered nearest neighbors. Those skilled in the art willrecognize that the line segments described above do not actually have tobe drawn on the golf ball. Rather, it is desirable for a computermodeling program to be capable of performing this operationautomatically.

Once each dimple's neighboring dimples are identified, the method of thepresent disclosure includes drawing a line from the center of eachdimple to the center of each of its neighboring dimples. Each lineconnecting the center of one dimple to the center of a neighboringdimple is referred to as a dimple line. The dimple lines for the set ofthe three neighboring dimples form a triangle. The resulting triangledefines the fret area in which the three-dimensional shaped fret areawill be formed. In the next step, the method of the present disclosureincludes identifying a centroid of the area enclosed by the resultingtriangle. The centroid of the triangle is the point that defines theapex of the fret area.

FIG. 10 is an illustration of three neighboring dimples on the golf ballsurface and the corresponding triangle formed by a set of threeneighboring dimple lines with an apex point defined therein. As shown inFIG. 10 , three neighboring dimples D₁, D₂, and D₃ on the golf ballsurface 10 are selected. A dimple line L₁ is drawn connecting the centerof the dimple D₁ to the center of the dimple D₂. As can be seen in FIG.10 , dimples D₁ and D₂ are considered to be “neighboring” dimples sincetwo tangency lines (not shown) and the dimple line L₁ do not intersectanother dimple (or portion thereof). Dimple line L₂ is drawn connectingthe center of the dimple D₂ to the center of the dimple D₃. Dimples D₂and D₃ are considered to be “neighboring” dimples since two tangencylines (not shown) and the dimple line L₂ do not intersect another dimple(or portion thereof). Dimple line L₃ is drawn connecting the center ofthe dimple D₃ to the center of the dimple D₁. Dimples D₃ and D₁ areconsidered to be “neighboring” dimples since two tangency lines (notshown) and the dimple line L₃ do not intersect another dimple (orportion thereof). As illustrated, dimple lines L₁, L₂, and L₃ for theset of three neighboring dimples, D₁, D₂, and D₃, form a triangle 70.The triangle 70 defines the fret area in which the three-dimensionalshaped fret area will be formed. The area enclosed by the triangle 70has a centroid 72. The centroid 72 is the point that defines an apex ofthe three-dimensional shaped fret area.

Once the centroid of the triangle, for example, the apex point, isidentified, the method of the present disclosure involves determiningthe edge origins of the triangle. An “edge origin,” as used herein,refers to any point along a dimple line that is located outside of theperimeter of any one of the neighboring dimples. An edge origin is notconsidered an edge of the three-dimensional shaped fret area. To form anedge of the three-dimensional shape, the method includes drawing an edgeline from an edge origin to the apex point. The edge line drawn from theedge origin to the apex point forms one edge of the shape. Any number ofedges and vertices may be drawn from the various edge origins to theapex point depending on the desired shape of the three-dimensionalformation, as discussed above.

FIG. 11 is an illustration of a three-dimensional irregular pyramidshaped fret area designed by drawing three edge lines from edge originsto the apex point of the fret area. As shown in FIG. 11 , edge lines canoriginate at any of the edge origins on the triangle 70. The edgeorigins along triangle 70 include any point along dimple line L₁ that islocated outside of the perimeter of each of neighboring dimples D₁ andD₂; any point along dimple line L₂ that is located outside of theperimeter of each of neighboring dimples D₂ and D₃; and any point alongdimple line L₃ that is located outside of the perimeter of each ofneighboring dimples D₃ and D₁. In the illustrated embodiment, edge lineE₁ is drawn from an edge origin along dimple line L₁ to an apex point A.Edge line E₂ is drawn from an edge origin along dimple line L₂ to theapex point A. Edge line E₃ is drawn from an edge origin along dimpleline L₃ to the apex point A. The three edge lines E₁, E₂, and E₃ form athree-dimensional irregular pyramid shaped fret area 80 having threeedges that meet at the apex point A.

In further embodiments, the method of the present disclosure may includeforming an apex surface about the centroid of the triangle. After thecentroid of the triangle, for example, the apex, is identified, an apexsurface may be drawn about the apex. In this embodiment, the apexsurface has a center of mass coincident with the apex point. The apexsurface may be drawn to have any shape discussed above in the precedingsection. In some embodiments, the apex surface has a polygonal shape.Once the apex surface is drawn such that its center of mass iscoincident with the apex point, edge lines can be drawn from the edgeorigins to the perimeter of the apex surface (rather than to the apexpoint as described above).

FIG. 12 is an illustration of an apex surface defined within thetriangle 70. After the centroid 72 of the area enclosed by the triangle70 is identified, an apex surface S is drawn about the centroid 72 suchthat its center of mass is coincident with the centroid 72 (e.g., theapex point). In the illustrated embodiment, the apex surface S is atriangle. The edges of the triangle are formed around the centroid 72 sothat the triangle's center of mass is positioned at the centroid 72.Edge lines can then be drawn from any edge origin along dimples linesL₁, L₂, and L₃ to the perimeter of the apex surface S. Examples ofresulting three-dimensional truncated irregular pyramid shaped fretareas formed in accordance with this embodiment of the presentdisclosure are illustrated in FIGS. 5, 6, and 7 (which are described indetail above).

The steps of the methods described herein may be repeated to formadditional three-dimensional shaped fret areas on the golf ball surface.For instance, the steps may be repeated to form three-dimensional shapedfret areas over one or more portions of the surface of the golf ball. Inother embodiments, the steps may be repeated to form three-dimensionalshaped fret areas over the entire surface of the golf ball.

The methods disclosed herein have been illustrated with golf ballsurfaces utilizing dimples having a circular plan shape. In theillustrated embodiments, the three-dimensional shaped fret areas aredesigned by using three neighboring dimples. However, as will beappreciated by those skilled in the art, the methods described hereincan be adapted for use on golf ball surfaces having various other dimplegeometries. Indeed, any number of neighboring dimples may be used todesign three-dimensional shaped fret areas depending on the dimplegeometry. For example, the methods disclosed herein can be utilized toform three-dimensional shaped fret areas on golf ball surfaces withdimples having a rectangular plan shape. In this embodiment, thethree-dimensional shaped fret areas may be designed by using fourneighboring dimples.

Golf Ball Construction

The three-dimensional shaped fret areas according to the presentdisclosure may be used with practically any type of ball construction.For instance, the golf ball may have a two-piece design, a double cover,or veneer cover construction depending on the type of performancedesired of the ball. Other suitable golf ball constructions includesolid, wound, liquid-filled, and/or dual cores, and multipleintermediate layers.

Different materials may be used in the construction of golf ballsaccording to the present disclosure. For example, the cover of the ballmay be made of a thermoset or thermoplastic, a castable or non-castablepolyurethane and polyurea, an ionomer resin, balata, or any othersuitable cover material known to those skilled in the art. Conventionaland non-conventional materials may be used for forming core andintermediate layers of the ball including polybutadiene and otherrubber-based core formulations, ionomer resins, highly neutralizedpolymers, and the like.

The golf balls of the present disclosure may be formed using a varietyof application techniques. For example, the golf ball layers may beformed using compression molding, flip molding, injection molding,retractable pin injection molding, reaction injection molding (RIM),liquid injection molding (LIM), casting, vacuum forming, powder coating,flow coating, spin coating, dipping, spraying, and the like.Conventionally, compression molding and injection molding are applied tothermoplastic materials, whereas RIM, liquid injection molding, andcasting are employed on thermoset materials.

The golf balls and methods described and claimed herein are not to belimited in scope by the specific embodiments herein disclosed, sincethese embodiments are intended as illustrations of several aspects ofthe disclosure. Any equivalent embodiments are intended to be within thescope of this disclosure. Indeed, various modifications of the golfballs and the methods in addition to those shown and described hereinwill become apparent to those skilled in the art from the foregoingdescription. Such modifications are also intended to fall within thescope of the appended claims. All patents and patent applications citedin the foregoing text are expressly incorporated herein by reference intheir entirety. Any section headings herein are provided only forconsistency with the suggestions of 37 C.F.R. § 1.77 or otherwise toprovide organizational queues. These headings shall not limit orcharacterize the invention(s) set forth herein.

1. A golf ball having a substantially spherical surface, comprising: aplurality of dimples on the spherical surface and a plurality of fretareas defined therebetween, wherein at least one fret area on thespherical surface comprises a three-dimensional irregular pyramid shapehaving a base formed of curved edges, the curved edges corresponding toedges of the dimples surrounding the fret area, and at least three edgesextending continuously upwardly from the base formed of the curved edgesand meeting at an apex point, and wherein the three-dimensionalirregular pyramid shape has a height defined as the radial distancebetween the apex point and a phantom sphere having a radius.
 2. The golfball of claim 1, wherein the three-dimensional irregular pyramid shapedfret area is surrounded by three dimples of the plurality of dimples. 3.The golf ball of claim 1, wherein the radius is greater than about 0.84inches.
 4. The golf ball of claim 1, wherein the radius is less thanabout 0.84 inches and the sum of the radius and the height is greaterthan about 0.84 inches.
 5. The golf ball of claim 1, wherein thethree-dimensional irregular pyramid shape has a total surface area ofabout 0.001 square inches to about 0.008 square inches.
 6. The golf ballof claim 1, wherein the height ranges from about 0.002 inches to about0.025 inches.
 7. A golf ball having a substantially spherical surface,comprising: a plurality of dimples on the spherical surface and aplurality of fret areas defined therebetween, wherein at least one fretarea on the spherical surface comprises a three-dimensional truncatedirregular pyramid shape having at least three edges meeting at an apexsurface, wherein the apex surface is a planar surface having a center ofmass coincident with an apex point of the three-dimensional truncatedirregular pyramid shape, and wherein the three-dimensional truncatedirregular pyramid shape has a height defined as the radial distancebetween the apex surface and a phantom sphere having a radius.
 8. Thegolf ball of claim 7, wherein the apex surface has a polygonal shapeformed of at least three edges.
 9. The golf ball of claim 8, wherein theapex surface has a triangular shape.
 10. The golf ball of claim 7,wherein the apex surface comprises a non-polygonal shape formed of acombination of line segments and curvatures.
 11. The golf ball of claim7, wherein the apex surface has a surface area ranging from about 0.0002square inches to about 0.001 square inches.
 12. The golf ball of claim7, wherein the three-dimensional truncated irregular pyramid shaped fretarea is surrounded by three dimples of the plurality of dimples.
 13. Thegolf ball of claim 7, wherein the height ranges from about 0.005 inchesto about 0.020 inches.
 14. The golf ball of claim 11, wherein thesurface area of the apex surface accounts for about 5 percent to about15 percent of the total surface area of the three-dimensional truncatedirregular pyramid shape.
 15. The golf ball of claim 7, wherein theradius of the phantom sphere is (i) greater than about 0.84 inches or(ii) less than about 0.84 inches but the sum of the radius and theheight is greater than about 0.84 inches. 16.-20. (canceled)
 21. A golfball having a substantially spherical surface, comprising: a pluralityof dimples on the spherical surface and a plurality of fret areasdefined therebetween, wherein at least one fret area on the sphericalsurface comprises a three-dimensional irregular pyramid shape having abase formed of curved edges, the curved edges corresponding to edges ofthe dimples surrounding the fret area, and at least three edgesextending continuously upwardly from the base formed of the curved edgesand meeting at an apex point. 22.-23. (canceled)
 24. The golf ball ofclaim 21, wherein the three-dimensional irregular pyramid shape has aheight defined as the radial distance between the apex point and aphantom sphere having a radius, and the height ranges from about 0.002inches to about 0.025 inches.
 25. (canceled)
 26. The golf ball of claim21, wherein the three-dimensional irregular pyramid shaped fret area issurrounded by three dimples of the plurality of dimples.